Ultrasound is an ideal imaging modality for underfluid navigation, diagnosis, and therapy. Larger fields of view will enhance application and versatility of these functions. Current ultrasound catheters typically view in only one direction, either to the side or forward. Previous invention disclosures of ultrasound catheters, by Seward, et al. of the above listed patents, capable of viewing in more than one direction have used individual piezoelectric elements which have a limited field of view, e.g., (1) linear array of individual elements (rectangular shaped image), (2) oscillating (i.e., nutate) element (sector shaped image with limited penetration), or (3) rotating element with reflecting mirror. Current ultrasound catheters also characteristically have high frequency transducer elements with limited penetration, which are principally used for imaging vessels (e.g., most typically the coronary arteries or peripheral veins and arteries), and have only incidentally been used for intra-cavitary imaging.
Accordingly, there is a need in ultrasound imaging catheter industry for a catheter providing a wide field of view, especially a wide field of view for underfluid navigation, diagnosis, and therapy.